“Connected lighting” refers to a system of luminaires which are controlled not by (or not only by) a traditional wired, electrical on-off or dimmer circuit, but rather via a wired or more often wireless network using a digital communication protocol. Typically, each of a plurality of luminaires, or even individual lamps within a luminaire, may each be equipped with a wireless receiver or transceiver for receiving lighting control commands from a lighting control device according to a wireless networking protocol such as ZigBee, Wi-Fi or Bluetooth (and optionally also for sending status reports to the lighting control device using the wireless networking protocol). For instance the lighting control device may take the form of a user terminal, e.g. a portable user terminal such as a smartphone, tablet, laptop or smart watch; or a static user terminal such as a desktop computer or wireless wall-panel. In such cases the lighting control commands may originate from a lighting control application (“app”) running on the user terminal, based on user inputs provided to the application by the user through a user interface of the user terminal (e.g. a touch screen or point-and-click interface). The user device may send the lighting control commands to the luminaires directly, or via an intermediate device such as a wireless router, access point or lighting bridge.
As connected lighting systems comprise a multitude of lighting devices or lighting nodes which are each individually controllable, it can be challenging for a user to create a desired light scene easily. It is known to use a connected lighting system to generate a lighting scene based on an image selected by a user. The image could be a still image or moving image. It could be a captured image (photograph or filmed video) or could be a user created image (e.g. drawing or animation). In such cases the lighting control application samples (“picks”) the colour and/or brightness values from one or more points or areas in the image, then uses these to set the colour and/or brightness levels of the illumination emitted by the luminaires providing the lighting scene. For instance the user may select a scene that has inspired him or her, such as an image of a forest or sunset, and the application sets the lighting based on this so as to recreate the colours of the image and therefore recreate the atmosphere of the scene shown in the image.
WO 2016/050539 discloses a method and system for generating and controlling a lighting scene of an environment based on a user preference and one or more images of the environment.
In one known implementation, the lighting control application automatically extracts the dominant colours from the image and assigns them randomly to individual lighting devices, thereby recreating a lighting scene giving a feel of that shown in the image. In another implementation, the lighting control application knows the positions or at least relative positions of the luminaires within the environment in question (e.g. room) and maps each to a corresponding point in the image. It then treats each of the luminaires as a “lighting pixel” to recreate an approximation of the image in the environment. In other more advanced implementations, image processing is used to identify segments within an image which can be mapped to specific lighting devices within an environment which are suitable for rendering that segment.